1. Field of the Invention
In one embodiment, the invention pertains to a timer in which household electrical power (in the United States-115 Volts AC; in some other countries 230 Volts AC or DC) is used as a switch to direct the household current to the appliance or light source. The switch can be regulated mechanically by a motor turning a gear train to rotate a dial. The dial may be provided with at least one On-Off cycle every twenty four hours. Multiple On-Off cycles ma also be provided to be operated by the single dial. Alternatively, one or more on-off cycles may be operated by digitally programming a central processing unit (“CPU”) to operate an electronic, or mechanical switch. Electrical energy for either the motor or digital programming can be provided by the household current, optionally suitably transformed or inverted to provide acceptable voltage of either AC or DC to operate the motor/CPU. In conditions where the household current is interrupted due to storms, accidents or other conditions, the timer of the invention is operated by a self-contained rechargeable battery. This self-contained battery will continue to operate the motor or CPU, as necessary, to keep the timer of the invention synchronous with external time and maintain the preset On-Off cycle(s). Of course, the rechargeable battery of the timer will not have the capacity to supply the household current to the appliance/light, but will turn On, and/or turn Off the output receptacle, even though the household current is not being applied to the timer. In a further embodiment, the timer can also charge external rechargeable battery(s), which external battery(s) may be independent of the tuning circuit and operation of the On-Off switching functions, or alternatively, may also aid in providing energy to the timer itself when the household power is interrupted.
2. Description of the Related Art
In a most simply form, timers are known to transfer household electrical supply from a source of suitable electric current, to an electrically powered device, such as an appliance or light. One such device is shown in U.S. Design Pat. No. D380,396, the entire disclosure of which is hereby incorporated by reference. As shown in FIG. 1 herein (Prior Art) the timer 8 is provided in a case 10, which houses a motor (not shown) to rotate a dial 12. The dial 12 may be provided with suitable indicia 13 representing units of time, such as hours and subdivisions thereof. Mechanically operated actuators 14, 16, 18, 20 may be placed about the periphery of dial 12, in order to mechanically operate a switch 25 to turn the switch 25 either On or turn the switch 25 Off to connect, or alternatively, interrupt the connection of the household power supply to the output receptacle 24. By having a number of such actuators 14, 16, 18 and 20 (or more or less, as desired) multiple On-Off cycles can be regulated by the timer. Alternatively, a digital clock circuit may be used to turn the switch On-Off to connect/interrupt the household electrical supply to the output receptacle in response to an integrated circuit (IC) or a programmable CPU (not shown) that provides even greater flexibility in the number of On-Off cycles that can be provided to the appliance timer.
As shown in FIG. 2 (Prior Art) the household electrical supply may be obtained by inserting prongs (such as prong 22, 23) into a source of household electrical supply, such as a receptacle (not shown) which is the source of the household electrical current. A plug (not shown) of the appliance/light may be inserted into output receptacle 24 in case 10. Although a conventional United States polarized receptacle is illustrated in FIG. 2, it should be understood that in the invention, the receptacle may include a grounding opening; or may be configured for other countries, i.e., any of the conventional 220 Volt AC or DC systems. Upon actuation of a switch 25 by any of the actuators 14, 16, 18 or 20, an electrical connection is made between prongs 22, 23 and output receptacle 24 permitting power to flow to the appliance/light to energize the same. Alternative the switch 25 may open terminating the electrical connection.
A problem with the prior art device illustrated in FIGS. 1-2 is the fact that any interruption of the household current will cause the motor to cease rotation thereby throwing the timer of the prior art out of synchronicity with external time. Upon re-establishment of the household current, the motor will begin to operate as normal, but because of the lack of continuous operation, the timer will now be asynchronous with external time. Thus, the actuators will not operate as desired to actuate the appliance/light at the desired time, but will turn the switch 25 On or Off at inappropriate times.
Heretofore, there has not been an appliance/light timer to overcome this problem.